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 What’s New in UML2  |  Short Talk  |  © 2006 by IBM; made available under the EPL v1.0
Challenges
§Since the specification has been at various stages of finalization, the API has been a moving target
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§Aspects of the standard metamodel (redefinition, subsets/supersets, unions) made the mapping to Java™ and XMI non-trivial
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§There were a number of errors in the specification which, until fixed, made the API and XMI schema difficult to use
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§Compliance points for UML are a subject of debate within the modeling community